2G6 CYPKlNlDiE. 



very similar to the Tench, but thicker, ventricose, and with the scales 

 small. The head is rather large, conical ; the snout obtuse, the 

 crown flattened ; eyes rather large, prominent, with the iris golden ; 

 iipper lip protractile, projecting over the lower, which is short. Sides 

 of body thick and convex ; back rounded, olive — resembling the 

 Tench in colour and the smalLiess of the scales. Belly white, slightly 

 silvery ; lateral line curving towards the belly and becoming straight 

 upon the tail ; dorsal situated far back on the body, with a sheath on 

 the base. Pectorals soft, red, with a thick caruncle at the base, of 

 a blood-red hue. Ventrals remote, small, straight, and red ; anal 

 removed further bacl^ than dorsal, transparent and reddish ; caudal 

 forked, olive-brown." 



Steller, from whose MS. this description is taken, found this fish 

 in stagnant waters along the banks of the ^iver Lena. 



62. LEUCOSOMUS *. 



Leucosomus, part., Heckel, in Utilise ffger's Reis. i. 1841, p. 1042. 

 Pogonichthys, Girard, Proc. Ac. Nat. Sc. Philad. 1854, p. 136. 

 Cheilouemus, (Baird) Storer, Mem. Amer. Acad. 1855. p. 280. 

 Mylocheilus, Agassiz, Sillwi, Journ. 1855, xix. p. 2-'51, 

 Leucosomus, Pogonichthys, Semotilus {Rajin.), Nocomis et Mylo- 

 cheilus, Girard, I. c. 1856, p. 189 et seq. 



Scales of moderate or small size ; lateral line present, running 

 along the middle of the side of the tail. Dorsal fin short, without 

 spinous ray, commencing opposite, or nearly opposite, to the ventral. 

 Anal fin short. Mouth anterior or subanterior ; intermaxillaries 

 protractile. A very small barbel at the extremity of the maxillary. 

 Lower jaw with rounded margin and with the labial folds well de- 

 veloped laterally. Gill-rakers short; pseudobranchiae. Pharyn- 

 geal teeth in a double series. 



North America. 



* 1. Leucosomus dissimilis, Girard, Proc. Ac. Nat. Sc. Philad. 1856, p. 189 ; 



or V. S. cf Pac. B. li. Rvped. Fish. p. 250. — Upper Missouri. 

 2. pallidus, Girard, I.e. 1°, p. 190 ; and /.c. 2°, p. 251, pi. 61. figs. 6- 



10. — Antelope Creek, Arkansas. (Appears to be closely allied to, if not 



identical with, Z. corporalis.) 

 o. incrassatus, Girard, I. c. 1° ; and I. c. 2', p. 252, pi. 61. figs. 1-5. — 



Twenty miles west of Choctaw Agency. 



4. Semotihis macrocephalus, Girard, I.e. 1°, p. 204; Leucosomus macro- 



cephalus, Girard, I. c. 2°, p. 252. — Fort Pierre, Nebraska. 



5. Semotilus speciosus, Girard, I. c. 1°; and /, c. 2°, p. 283, pi. 01. figs. Il- 



ia. — Platte River. 



6. Nocomis nebrascensis, Girard, I. c. 1°, p. 190 ; and I. c. 2°, p. 254. — 



Sweetwater, Nebraska River. 



7. bellicus, Girard, I. c. 1°, p. 213. — Black Warrior River, Alabama. 



8. Leuciscus pulchelloides, Ayres, Proc. Bost. Soc. Nat. Hist. iii. p. 157. — 



Connecticut.-^L. lat. 00. 



